This invention relates to display devices that project an image. More particularly, the present invention relates to projection-type display devices that may operate on battery power and increase usage flexibility.
Most computer systems employ a display device to output video information to one or more users. Desktop computers, laptop computers, personal digital assistants (PDAs), video game consoles, cellular telephones and digital video cameras output video information to a number of video display technologies.
Cathode ray tube (CRT) monitors evolved from CRT televisions. Such monitors are heavy and large for their screen size relative to other display technologies. The footprint of a CRT monitor monopolizes usable space on a table or desk. The weight and size of CRT monitors prevents portable use.
Liquid crystal display (LCD) displays are currently the leading display technology for portable applications, but limit display area size to the dimensions of a device they are included with.
Projection-type display systems offer image sizes having diagonal spans up to 30 feet. Projected images allow numerous people to simultaneously view a projected image.
A recent increase in projector sales has been motivated by boardroom and classroom usage where numerous people in a large space can simultaneously view a projected image. Consumer demand in this aspect of the market has led manufacturers to evolve projectors towards increasingly powerful and feature-rich products.
Portability for the current designs is already hampered by size and weight. Moreover, due to the high power consumption of the current designs, consumers are forced to rely on AC connectivity to a wall outlet or other fixed power supply. This connectivity requirement handicaps portable usage.
Based on the foregoing, it should be apparent that portable visual output options are still limited; and that alternative portable visual output options would be desirable.